Oligarchy

Oligarchy is a form of power structure in which power effectively rests with a small number of people. These people could be distinguished by royalty, wealth, family ties, education, corporate, or military control. Such states are often controlled by a few prominent families who typically pass their influence from one generation to the next. But inheritance is not a necessary condition for the application of this term.

A hereditary oligarchy is an aristocracy. A military oligarchy is a hoplocracy. An economic oligarchy is a plutocracy. Most oligarchies become hoplocracies and plutocracies by default, regardless of their origin.